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The gravitational field of a massive, filamentary ring is considered. We provide an analytic expression for the gravitational potential and demonstrate that the exact gravitational potential and its gradient, thus the gravitational force-field, is not central. Hence it is a good candidate to discuss the difference between the concepts of center of mass and center of gravity. We focus on other consequences of reduced symmetry, e.g., only the $z$-component of the angular momentum is conserved. However, the remnant high symmetry of this system also ensures that there are special classes of motions which are restricted to invariant subspaces, thus, depending on the initial condition, the dynamics of a point particle is integrable. We also show that periodic orbits in the equatorial plane external to the ring are possible, but only if the angular momentum is above a threshold value. In this case the orbits are stable.
A static and circularly symmetric lens characterized by mass and scalar charge parameters is constructed. For the small values of the scalar charge to the mass ratio, the gravitational lensing is qualitatively similar to the case of the Schwarzschild
When a massive quantum body is put into a spatial superposition, it is of interest to consider the quantum aspects of the gravitational field sourced by the body. We argue that in order to understand how the body may become entangled with other massi
What gravitational field is generated by a massive quantum system in a spatial superposition? Despite decades of intensive theoretical and experimental research, we still do not know the answer. On the experimental side, the difficulty lies in the fa
Recently, the relation between Hawking radiation and gravitational anomalies has been used to estimate the flux of Hawking radiation for a large class of black objects. In this paper, we extend the formalism, originally proposed by Robinson and Wilcz
The presence of gravity generalizes the notion of scale invariance to Weyl invariance, namely, invariance under local rescalings of the metric. In this work, we have computed the Weyl anomaly for various classically scale or Weyl invariant theories,